8. The Bourne Ultimatum
Arguably cinema's greatest example of a series that has continually one-upped itself (ignoring the non-sequel The Bourne Legacy), The Bourne Identity was a potent, energetic mystery thriller that helped establish Matt Damon as a credible action star. The sequel, changing out director Doug Liman for Paul Greengrass, was more of the same but
bigger and more exciting, with Greengrass' divisive "shaky cam" aesthetic giving the series a signature style that has been widely imitated since. The third film manages to again reinvent itself, pushing the thrills to even greater heights as Matt Damon's Jason Bourne finds himself confronting the U.S. agency who made him this seemingly unstoppable force of nature. With its intricate narrative, superb performances and exhilarating action (especially the scene in which Bourne kills an assassin with a tea towel), Ultimatum proved that even the third film in a series can be the best, rare though it is.